A certain kind of novelist cannot afford to avoid clichés. Last Orders is written in the voices of half a dozen characters, all of them elaborately involved in the events they narrate. Not one of them is "educated" or middle class. The novel expects us to imagine them as if they are speaking, though silently, to themselves. They can be defensive or evasive or awkward, but they must seem unstudied. None of the characters should know that he or she is in a novel.

We must not catch them sounding too original. So not only do we get clichés in the novel's dialogue, where we might expect them, but also in the narrative. "I've heard it a hundred times before." "You've got another think coming." "He was putty in my hands." These are not fragments of speech, where cliché is a necessary currency. These are from the narratives of Swift's leading characters, their interleaved monologues.

Clichés are often knowing, carrying the speaker's awareness that he or she is resorting to a formula. Ray tells us how the break-up of his marriage happened after the death of his father-in-law and his daughter's emigration to Australia. "Never rains but." He knows that we know the words - but then, as the cliché has it, we know the feeling. No need to say more. The truism is the more appropriate as the two preceding disasters do indeed push his wife to leave. Clichés in this novel are not thoughtless phrases; they are the regretfully or sardonically repeated truths of life.

"It ain't much to write home about," Ray says when he sees Margate pier, from where he must scatter Jack's ashes. It is a ruefully true formula, for also in his thoughts are all the unwritten or undelivered messages of his life: the postcard that did not reach his father before he died, the letters he never wrote to his daughter. He thinks of her in Australia and of what she must think about his failure to keep in touch. "Out of sight, out of mind". But she is not out of his mind. The cliché is a cover for the truth.

Perhaps Swift has learned from American fiction, often confident in its use of cliché. It has been pointed out that Last Orders owes much to William Faulkner's 1930 novel As I Lay Dying. This is in a line of American novels that convince by their colloquial rhythms, from Huckleberry Finn to The Catcher in the Rye. The imagined speakers of these works are full of re-animated clichés, testing limited vocabularies on the unlimited perplexities of life.

Several of the first reviewers praised Last Orders for its imagining of "ordinary" people and lives. The adjective is one George Eliot liked to use for the subject matter of her novels, and Swift would probably accept it. Clichés might just be the novelist's shortcut to ordinariness - to colloquialism or authenticity. But here they are discriminating. Different speakers use them differently.

Vince, the car salesman, gets into resentful muddles with his clichés. When life is difficult, he says, you've always got your car. "If it hadn't been invented, we'd have had to invent it". Meanwhile Vic, the undertaker, artfully bends his truisms. Visiting the memorial to the Navy dead at Chatham he thinks, "Even on land we're all at sea". He calls retirement "taking your nose from the grindstone". Professionally speaking, his clichés are morbidly comic. Reflecting on the unexpected meetings that "come with the territory", he says, "You never know who you might bump into, you never know whose toes you might tread on".

Common phrases are often apt in a novel about what is most common: mortality. Characters are brought to know that their sharpest pains are indeed but common and all the sharper for being ordinary. Not even love is as hedged by clichés as death. Near its end, the novel sums this up with a joke about a cliché, a piece of wisdom that Jack remembers from his trade as a butcher. "What you've got to understand is the nature of the goods. Which is perishable." True enough.

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